The invention relates to a system for providing two different controlled tensions to a flexible tape moving between a first and second hub at a greatly varying rate of speed, and more particularly, relates to a tension control apparatus system for loading magnetic recording tape into tape cassettes.
In a tape cassette loader, a predetermined length of tape is paid out from a spool and taken up and loaded within a tape cassette. Such cassette loaders include a single source of tension regulating the tension between the supply spool and the spool of the tape cassette. See for example U.S. Pat. No. 3,753,834 issued to James L. King on Aug. 21, 1973.
In the art of tape cassette loading, the speed at which a cassette may be loaded with tape determines the quantity of cassettes produceable per machine in a given work day. To produce more cassettes, more machines would be necessary resulting in higher costs for machines, labor in operating the machines, maintenance and energy needs. It would be highly desirable to increase the speed at which the present state of the art machine can load tape into a single cassette.
However, as the cassette spool within the cassette is driven at extremely high rates of speed in order to wind tape extremely fast into the cassette, the tape bearing surfaces inside the cassette begin to heat up from frictional drag of the tape and of the spool of tape building up within the cassette. For example, the slip sheet within the cassette may be abraided through to the cassette shell by contact with the tape, and the shell may begin to melt. Also, rollers and tape guide surfaces within the cassette will heat up and begin to melt during high speed winding. These heating and abraiding effects depend on the speed of winding and the tension of the tape.
Therefore, it would be highly desirable to provide apparatus which permits high speed loading of magnetic tape into a conventional tape cassette. The present invention provides such high speed loading by controlling the tension applied to the tape during loading in order to reduce the rate of heat transfer to the cassette and to reduce abraiding effects to the cassette.